xref: /openbmc/linux/arch/powerpc/perf/e500-pmu.c (revision 99a15348)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Performance counter support for e500 family processors.
4  *
5  * Copyright 2008-2009 Paul Mackerras, IBM Corporation.
6  * Copyright 2010 Freescale Semiconductor, Inc.
7  */
8 #include <linux/string.h>
9 #include <linux/perf_event.h>
10 #include <asm/reg.h>
11 #include <asm/cputable.h>
12 
13 /*
14  * Map of generic hardware event types to hardware events
15  * Zero if unsupported
16  */
17 static int e500_generic_events[] = {
18 	[PERF_COUNT_HW_CPU_CYCLES] = 1,
19 	[PERF_COUNT_HW_INSTRUCTIONS] = 2,
20 	[PERF_COUNT_HW_CACHE_MISSES] = 41, /* Data L1 cache reloads */
21 	[PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = 12,
22 	[PERF_COUNT_HW_BRANCH_MISSES] = 15,
23 	[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = 18,
24 	[PERF_COUNT_HW_STALLED_CYCLES_BACKEND] = 19,
25 };
26 
27 #define C(x)	PERF_COUNT_HW_CACHE_##x
28 
29 /*
30  * Table of generalized cache-related events.
31  * 0 means not supported, -1 means nonsensical, other values
32  * are event codes.
33  */
34 static int e500_cache_events[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
35 	/*
36 	 * D-cache misses are not split into read/write/prefetch;
37 	 * use raw event 41.
38 	 */
39 	[C(L1D)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
40 		[C(OP_READ)] = {	27,		0	},
41 		[C(OP_WRITE)] = {	28,		0	},
42 		[C(OP_PREFETCH)] = {	29,		0	},
43 	},
44 	[C(L1I)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
45 		[C(OP_READ)] = {	2,		60	},
46 		[C(OP_WRITE)] = {	-1,		-1	},
47 		[C(OP_PREFETCH)] = {	0,		0	},
48 	},
49 	/*
50 	 * Assuming LL means L2, it's not a good match for this model.
51 	 * It allocates only on L1 castout or explicit prefetch, and
52 	 * does not have separate read/write events (but it does have
53 	 * separate instruction/data events).
54 	 */
55 	[C(LL)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
56 		[C(OP_READ)] = {	0,		0	},
57 		[C(OP_WRITE)] = {	0,		0	},
58 		[C(OP_PREFETCH)] = {	0,		0	},
59 	},
60 	/*
61 	 * There are data/instruction MMU misses, but that's a miss on
62 	 * the chip's internal level-one TLB which is probably not
63 	 * what the user wants.  Instead, unified level-two TLB misses
64 	 * are reported here.
65 	 */
66 	[C(DTLB)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
67 		[C(OP_READ)] = {	26,		66	},
68 		[C(OP_WRITE)] = {	-1,		-1	},
69 		[C(OP_PREFETCH)] = {	-1,		-1	},
70 	},
71 	[C(BPU)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
72 		[C(OP_READ)] = {	12,		15 	},
73 		[C(OP_WRITE)] = {	-1,		-1	},
74 		[C(OP_PREFETCH)] = {	-1,		-1	},
75 	},
76 	[C(NODE)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
77 		[C(OP_READ)] = {	-1,		-1 	},
78 		[C(OP_WRITE)] = {	-1,		-1	},
79 		[C(OP_PREFETCH)] = {	-1,		-1	},
80 	},
81 };
82 
83 static int num_events = 128;
84 
85 /* Upper half of event id is PMLCb, for threshold events */
86 static u64 e500_xlate_event(u64 event_id)
87 {
88 	u32 event_low = (u32)event_id;
89 	u64 ret;
90 
91 	if (event_low >= num_events)
92 		return 0;
93 
94 	ret = FSL_EMB_EVENT_VALID;
95 
96 	if (event_low >= 76 && event_low <= 81) {
97 		ret |= FSL_EMB_EVENT_RESTRICTED;
98 		ret |= event_id &
99 		       (FSL_EMB_EVENT_THRESHMUL | FSL_EMB_EVENT_THRESH);
100 	} else if (event_id &
101 	           (FSL_EMB_EVENT_THRESHMUL | FSL_EMB_EVENT_THRESH)) {
102 		/* Threshold requested on non-threshold event */
103 		return 0;
104 	}
105 
106 	return ret;
107 }
108 
109 static struct fsl_emb_pmu e500_pmu = {
110 	.name			= "e500 family",
111 	.n_counter		= 4,
112 	.n_restricted		= 2,
113 	.xlate_event		= e500_xlate_event,
114 	.n_generic		= ARRAY_SIZE(e500_generic_events),
115 	.generic_events		= e500_generic_events,
116 	.cache_events		= &e500_cache_events,
117 };
118 
119 static int init_e500_pmu(void)
120 {
121 	if (!cur_cpu_spec->oprofile_cpu_type)
122 		return -ENODEV;
123 
124 	if (!strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc/e500mc"))
125 		num_events = 256;
126 	else if (strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc/e500"))
127 		return -ENODEV;
128 
129 	return register_fsl_emb_pmu(&e500_pmu);
130 }
131 
132 early_initcall(init_e500_pmu);
133